Feed mechanisms for advancing a strip of terminals in a terminal applicator are either powered by a separate air cylinder or are mechanically coupled to the ram so that movement of the ram effects operation of the feed mechanism. An example of an air cylinder powered feed system is disclosed in U.S. Pat. No. 4,970,889 which issued Nov. 30, 1990 to Phillips et al. However, feed mechanisms coupled to the ram are preferred in many instances because they are usually less expensive to manufacture. Examples of mechanical feed mechanisms are disclosed in U.S. Pat. Nos.: 3,184,950 which issued May 25, 1965 to Sitz; 3,673,847 which issued Jul. 4, 1972 to van de Kerkhof; 5,095,599 which issued Mar. 17, 1992 to Gloe et al,; and 5,483,739 which issued Jan. 16, 1996 to Smith et al. Both types of feed mechanisms utilize a feed finger that is attached to and carried by an arm that is moved so that the feed finger engages and advances a strip of terminals into and through the terminal crimping area of the applicator. The feed finger is adjustably positionable with respect to the crimping area so that the end point of the feed finger can be precisely positioned to accurately position the terminal in the crimping dies. Either the feed finger is slidingly coupled to the arm and can be moved to a desired position along the arm, or the feed finger is attached to the arm and the arm is slidingly coupled to another portion of the feed mechanism. In either case, once properly positioned, the feed finger is locked in place, usually by means of a set screw that frictionally engages the slide member, or some other part of the mechanism, and interferes with further sliding movement. This locking requires a substantial amount of force that can be obtained only by the use of tools that provide a mechanical advantage. However, during operation of the applicator, such locking devices are subjected to substantial vibrations and may fail to positively hold the feed finger in the desired position. When this occurs the feed finger very gradually moves out of proper position, resulting in miss-feeds that can damage both the product and the terminal applicator.
What is needed is a locking device that positively locks the feed finger in the desired position that is effective in the normal operating environment of the terminal applicator. The locking device should be operable without the use of tools.